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COMMITMENTS AND CONTINGENCIES (Tables) | 9 Months Ended
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Sep. 30, 2019
Southbridge Landfill |
Site Contingency [Line Items] |
Summary of Environmental Liability | The changes to the environmental remediation liability associated with the Southbridge Landfill are as follows:
| Nine Months Ended September 30, |  |
| 2019 |  | 2018
Beginning balance | $ | 5,173 |  |  | $ | 5,936 |
Accretion expense | 94 |  |  | 116 |
Obligations settled (1) | (556) |  |  | (612) |
Ending balance | $ | 4,711 |  |  | $ | 5,440 |
(1)Includes amounts that are being processed through accounts payable as a part of our disbursements cycle.
Potsdam Environmental Remediation |
Site Contingency [Line Items] |
Summary of Environmental Liability | A summary of the changes to the environmental remediation liability associated with the Potsdam environmental remediation liability follows:
| Nine Months Ended September 30, |  |
| 2019 |  | 2018
Beginning balance | $ | 5,614 |  |  | $ | 5,758 |
Obligations settled (1) | (1,764) |  |  | (98) |
Ending balance | $ | 3,850 |  |  | $ | 5,660 |
(1)Includes amounts that are being processed through accounts payable as a part of our disbursements cycle.

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